You’ve heard it before – toss old face paste. Here’s why: products that contain water and some nutrient source can give birth to bacteria, which (while it is rare) can cause infection. So keep your dry stash dry: exposing products with a low water content, such as lipstick and eye shadow, to agua can hasten their decline. And don’t hang onto mascara, which has the shortest lifespan. Stick with this schedule for a safer bag of beauty tricks:

Eyeliner
Lasts longer than some jobs. Toss pencils after about three years.

Eye Shadow
Kept dry, powders will stay safe for your peepers for up to three years.

Lipstick/Gloss
Wave a wet wonder wand for no longer than two years.

Mascara
Gooier than the rest, it doesn’t last long: chuck it after four months.